This invention relates to improvements in vehicle safety systems, in particular systems that may assist a driver in controlling a vehicle or that may be used as part of the control system for an autonomous vehicle.
It is known to provide various safety systems for vehicles, both passive safety systems and active safety systems. Indeed, recognizing that such systems can help reduce the number of fatalities on the road they are often mandatory equipment on new vehicles as many countries have legislation requiring the vehicles to be provided with those features.
Example of passive safety features for vehicles are seatbelts, airbags, pedestrian impact crumble areas and the like. The intention of these features is to protect the occupants of the vehicle, or pedestrians, from harm if an accident occurs. These features have been fitted to vehicle for a number of years now.
Active safety features, on the other, are capable of modifying the behavior of the vehicle alongside, or independently of the driver, in order to try to avoid an accident from happening. The increased use of electronic systems on the vehicle to control the steering, brakes and accelerator have made it possible for safety systems to control the movement of the vehicle. When combined with sensors fitted to the vehicle it is possible for a controller on the vehicle to determine that an accident is imminent and take some action.
An example of an active safety system that is fitted to a range of vehicles at present is automatic braking, in which the brakes are applied independent of the action of the driver if a controller fitted to the vehicle determines that a collision is likely. The controller may receive inputs from a range of sensors, including vehicle speed sensors and radar sensors that detect objects in the vehicles path. Another example of an active safety system is lane assist, in which the controller can adjust the steering of the vehicle independent of the driver so as to keep the vehicle within a lane of the highway.
Taking the idea of active system yet further are proposals for driverless (sometimes referred to as autonomous) vehicles which may perform some or all of the functions of the driver including steering, braking, accelerating and navigating the vehicle. The present invention is applicable to vehicles that are driven and also to fully or partially driverless vehicles